Reed, U.S. Pat. No. 4,506,988; Levine, U.S. Pat. No. 4,637,221; Carlson, U.S. Pat. No. 4,708,489; and Verkler, U.S. Pat. No. 4,828,398 are incorporated herein by reference as background art.
Processing appliances for softening ice cream have been provided before now, and generally, as shown in Carlson ""489 for example, have a container that is adapted to hold the ingredients that are to be processed, such as hard packed ice cream, and a rotatable auger that is fed into the container thereby displacing and working the ingredients, such as hard packed ice cream, therein to soften or otherwise blend them. Generally, the container and the auger are axially spaced from one another providing access to the opening of the container for filling it with the ingredients to be softened. Once all of the ingredients have been put into the container, the rotatable auger can be started and introduced into the container either by axial displacement of the auger or by axial displacement of the container. Such devices are typically large and generally employ complicated mechanisms to move the auger or the container axially into engagement with the other components to blend and soften the ice cream. As such, these devices are not suitable for home use.
Ice cream softening appliances for use in the home have been provided before now and generally, as shown in Verkler ""398 for example, have a container for holding ice cream and other ingredients and a rotatable auger that engages the edible ingredients in the container and thereby the causes the blending and softening of them. The device in Verkler ""398 includes an axially stationary auger supported on a frame and driven by a belt through the output of an electric motor. Initially, the container is axially displaced away from the auger providing access to the top of the container for the input of ingredients, such as hard packed ice cream. Once the ingredients have been put into the container, the auger started and the container is axially displaced toward the auger moving the ingredients and the auger into engagement with each other, facilitating the softening and blending of the ingredients.
In each of the foregoing devices, the auger has one or more lands that resemble large screw threads spirally extending along the axis of the auger. Before the engagement of the auger with the container, the rotating auger is fully exposed and could cause injury should an operator""s hand or piece of clothing get caught by the auger. Additionally, the mechanisms employed by the foregoing devices to move the container and the auger into engagement with each other expose the operator to pinch-points and other possible causes of injury. This is a significant disadvantage of these prior devices.
In commercial applications, the danger of injury may be minimized through training and supervision of the operators of such equipment. However, in devices intended and suitable for use in the home, such as Verkler ""398 for example, training and supervision are generally not possible. This is a significant disadvantage of devices intended for use in the home.
It will be appreciated that the containers in the foregoing devices include an inside surface that defines the work chamber. The product in the work chamber is displaced by the movement and rotation of the auger as it enters the work chamber. Once the auger is fully engaged with the container in the work chamber, the ingredients to be softened are sheared by the action of the auger relative to the inside surface of the work chamber. However, as the ingredients become softened and their temperature increases, the ingredients increasingly slip around the smooth inside surface of the work chamber. This reduces the efficiency of the auger by reducing the shearing action of the products between the auger and the work chamber. As such, the ingredients must be processed for an extended period to ensure that they will be sufficiently blended and that the final product will be smooth with a minimal number of hardened lumps in it.
In accordance with the present invention, a processing appliance for softening ice cream and other ingredients for use in the home is provided that avoids or minimizes the problems and difficulties encountered with the use of devices of the foregoing character, while promoting or maintaining the desired safe operation, simplicity of use, durability of construction, and economy of manufacture. More particularly in this respect, a processing appliance for softening ice cream and other ingredients for use in the home according to the invention includes a rotatable auger supported on a base that provides rotation thereto through an electric motor, a hopper for holding the ingredients, such as hard packed ice cream, a plunger assembly for urging the ingredients into engagement with the auger, and a nozzle for dispensing the softened and blended product. The hopper is supported on the base and has a processing portion that is generally coaxial with the auger. Extending transversely from the processing portion is a receiving portion. The receiving portion has an opening toward the top of it and is adapted to hold the ingredients before being processed by the auger. Adjacent the processing portion of the hopper and supported thereon coaxially with the auger is a nozzle. The nozzle has an opening at the end of it for the dispensing of the softened and blended product. The ingredients in the receiving portion of the hopper are urged toward the processing portion of the hopper and the auger by a rod and piston that is suitably adapted to travel the receiving portion.
The auger engages and is driven by the rotatable output of the base. The auger is a generally cylindrical screw with a tapered front end that has an outside profile defined by one or more lands spirally extending along the length of it. It will be appreciated that the lands have a lead defined as the axial distance traveled per revolution of the auger and that the lead of the lands may vary along the length of the auger. The cross-sectional area of the grooves of the auger may vary along the length of the auger.
The processing portion of the hopper includes an inside surface defining a processing passage. The nozzle also includes an inside surface defining a nozzle passage. The processing and nozzle passages together define a work chamber in which the auger is at least partially encapsulated, and in the preferred embodiment the auger is entirely encapsulated except for the portion exposed to the receiving portion of the hopper. Additionally, the nozzle may be adapted to force the softened and blended product to be dispensed in a downward direction out of the nozzle.
The work chamber defined by the inside surfaces of both the processing passage and the nozzle passages create an envelope that is closely fitted to the outside profile of the auger. A plurality of grooves extend longitudinally along the inside surface of both the processing passage and the nozzle passage. These grooves will provide the necessary rifling effect for displacing the ingredients forward by means of a rotating auger, and they will also create less wasteful space between the lands and grooves of the auger and the inside surface of the processing and nozzle passages. As such, a shorter auger and work chamber may be employed to provide the same blending and softening action. However, instead of grooves a plurality of ribs may extend longitudinally along the inside surface of both the processing passage and the nozzle passage. In this embodiment, the auger would ride on the ribs in the work chamber such that small pockets are formed between two adjacent ribs, the inside surface of the processing passage or the nozzle passage and the lands and grooves of the auger. These small pockets would provide significantly increased shearing action and recirculation of the ingredients being softened and blended over a work chamber that does not include such longitudinal ribs.
In operation, the ingredients to be blended and softened, such as hard packed ice cream, are placed into the hopper, the motor is energized and the plunger assembly is used to urge the ingredients into engagement with the auger. The piston of the plunger assembly is displaced through the receiving passage by pumping the handle of a ratcheting mechanism that rests atop the hopper. The lands and grooves of the auger shear the ingredients from the receiving portion of the hopper and carry them around the processing portion and along the auger into the nozzle portion filling the pockets between the ribs as the final, blended product is displaced. The action of the auger recirculates the product in and out of these pockets, increasing the shearing action of the ingredients as they travel toward the output end of the work chamber in the nozzle. A smooth, softened and blended product is extruded out of the end of the nozzle, resembling a product such as a soft serve ice cream that one gets at a commercial soft serve stand. It will be appreciated that the ingredients blended and processed by the subject device may include fillers such as cookies, fruits and/or candy. These fillers may be placed in alternate layers with the other ingredients in the receiving portion of the hopper and processed as discussed above, providing a soft serve product having the filler material broken up and blended within it.
Additionally, it will be appreciated that the subject device is intended for use with ingredients such as frozen ice cream. As such, the hopper, including both the receiving portion and the processing portion, and the nozzle may be insulated by air spaces or another suitable insulating medium to help in keeping the ingredients being processed near their freezing temperature during the entire process.
Accordingly, it is an outstanding object of the present invention to provide a processing appliance for softening ice cream for use in the home having a work chamber and auger arrangement of increased efficiency so that the size of the device may be minimized.
Another object is the provision of a processing appliance of the foregoing character in which the auger is fully encapsulated by the work chamber to minimize the possibility of injury to the operator of it.
Another object is the provision of a processing appliance of the foregoing character in which the auger and work chamber are axially stationary, eliminating the need for complicated mechanisms to move the auger and work chamber into engagement with each other.
Another object is the provision of a processing appliance of the foregoing character that is easy to operate, and simple to assemble, disassemble and clean.
A further object is the provision of a processing appliance of the foregoing character that comprises a minimal number of parts having a durable yet simple structure, thereby promoting the economic production of the appliance.